where is my "Team Explorer" or RTM vs SP

My Install:
Microsoft Visual Studio 2005
Version 8.0.50727.762 (SP.050727-7600)
Microsoft .NET Framework
Version 2.0.50727
Installed Edition: Enterprise
A CoWorker:
Microsoft Visual Studio 2005
Version 8.0.50727.42 (RTM.050727-4200)
Microsoft .NET Framework
Version 2.0.50727
Installed Edition: Enterprise

My coworker has Visual Studio 2005 Team Explorer 77633-163-9000041-41703
while I do not. This is a large company, so all pc's are "ghosted" and he
claims that he did not install anything himself.

1. what is the difference between the RTM and SP version?
2. Is Team Explorer now offered as a pluggin and where do I get it or do I
need to request the Team Foundation Server discs?

Thanks
--
kevin...